PACCAR PX-9 CM2350 (2013-17) Fault Code:1429 PID: SPN:4187 FMI:31 High Engine Temperature (HET) Shutdown Relay Driver Diagnostic Has Detected an Error – Condition Exists

Reason:
High Engine Temperature (HET) Shutdown Relay Driver Diagnostic Has Dectected An Error – Condition Exists

Effect:
The high engine temperature shutdown lamp will not turn on.

Circuit Description:
The high engine temperature shutdown lamp will indicate when the engine has reached a most severe level high coolant or intake manifold temperature. Fault Code 151 or 155 will trigger the high engine temperature shutdown lamp.

Component Location:
Refer to the OEM service manual for lamp location

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected an open on the lamp circuit.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
N/A

Possible Causes:
1) Open signal circuit or shorted to voltage source.
2) A signal shorted to ground in the harness
3) Open signal circuit in the OEM harness, connectors, or sensor